/* Copyright (C) 2021 MariaDB Corporation

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; version 2 of
   the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

#include <string>
using namespace std;

#include "functor_str.h"
#include "functioncolumn.h"
#include "utils_utf8.h"
using namespace execplan;

#include "rowgroup.h"
using namespace rowgroup;

#include "dataconvert.h"
using namespace dataconvert;

namespace funcexp
{

CalpontSystemCatalog::ColType Func_concat_oracle::operationType(FunctionParm& fp, CalpontSystemCatalog::ColType& resultType )
{
    // operation type is not used by this functor
    return fp[0]->data()->resultType();
}


// Returns the string that results from concatenating the arguments.
// concat_oracle() returns NULL all arguments are NULL.
// single arguments null is replaced by "".
//
string Func_concat_oracle::getStrVal(Row& row,
                              FunctionParm& parm,
                              bool& isNull,
                              CalpontSystemCatalog::ColType&)
{
	string ret;
    string tmp;
    stringValue(parm[0], row, isNull, ret);
    // Oracle Mode should replace NULL with "" unless all values are NULL
    if (isNull)
    {
        ret = "";
        isNull = false;
    }
    // TODO: do a better job of cutting down the number re-allocations.
    // look at Item_func_concat::realloc_result for ideas and use 
    // std::string:resize() appropriatly.
    for ( unsigned int id = 1 ; id < parm.size() ; id++)
    {
		stringValue(parm[id], row, isNull, tmp);
	    if (isNull)
	    {
	        tmp = "";
	        isNull = false;
	    }
        ret.append(tmp);
    }

    return ret;
}

} // namespace funcexp
// vim:ts=4 sw=4: